A case of immune checkpoint inhibitor-associated gastroenteritis detected by ultrasonography

Immune checkpoint inhibitor-associated gastritis: Patterns and management

Immune checkpoint inhibitors (ICIs) are widely used due to their effectiveness in treating various tumors. Immune-related adverse events (irAEs) are defined as adverse effects resulting from ICI treatment. Gastrointestinal irAEs are a common type of irAEs characterized by intestinal side effects, such as diarrhea and colitis, which may lead to the cessation of ICIs. Although irAE gastritis is rarely reported, it may lead to serious complications such as gastrorrhagia. Furthermore, irAE gastritis is often difficult to identify early due to its diverse symptoms. Although steroid hormones and immunosuppressants are commonly used to reverse irAEs, the best regimen and dosage for irAE gastritis remains uncertain. In addition, the risk of recurrence of irAE gastritis after the reuse of ICIs should be considered. In this editorial, strategies such as early identification, pathological diagnosis, management interventions, and immunotherapy rechallenge are discussed to enable clinicians to better manage irAE gastritis and improve the prognosis of these patients.

Immune-mediated Gastritis in a Patient with metastatic Lung Cancer due to Therapy with the immune Checkpoint Inhibitor Pembrolizumab - Differences and Similarities in Comparison to "endogenous" autoimmune Type A Gastritis and a review of literature

Immune checkpoint inhibitors are increasingly used in advanced malignant diseases and are well-known for their good results. With the blockade of immune checkpoints, the probability of immune-related adverse events is also increased.We present a 54-year-old female patient with advanced NSCLC. She was treated with pembrolizumab and developed a stable disease under therapy. After six cycles, she presented with massive epigastric pain to our emergency department. Gastroscopy showed severe erosive-fibrinous pangastritis without the involvement of the esophagus, duodenum, or other immune-related adverse effects. Histology showed the complete destruction of the gastric mucosa. We concluded an immune-mediated gastritis by pembrolizumab, after the exclusion of other differential diagnoses.Despite treatment with prednisolone and marked improvement of her symptoms, the mucosa was never fully reconstituted into a healthy mucosa.Furthermore, we collected published reports of similar cases and conducted a comparison with features of a typical, endogenous type A gastritis to highlight similarities and differences.

An unusual case of immune-related gastritis in one patient receiving toripalimab therapy

PD-1 inhibitors contribute to immune response against malignancies. These drugs also result in serial side effects. Here the authors report a case of immune-related gastritis induced by PD-1 inhibitor. A female with metastatic lung cancer developed severe epigastric pain and acid reflux during treatment with toripalimab. She underwent several gastroscopies, which showed progressively worse gastritis. After discontinuing toripalimab, those symptoms were resolved. This rare report highlights gastritis associated with toripalimab, describes the symptoms and histology features and records the progression of this side effect and the corresponding treatment. Based on the improvement after toripalimab withdrawal, the authors believed that she had autoimmune gastritis caused by toripalimab. This case reminds us that correct diagnosis and proper management are critical to patients undergoing treatment with PD-1 inhibitors.

Clinical Characteristics and Outcomes of Gastritis Associated With Immune Checkpoint Inhibitors: Scoping Review

Among immune-related adverse events associated with immune checkpoint inhibitors, immune-mediated gastritis (IMG) has been rarely described in the literature and has not yet been well characterized. This scoping review aimed to characterize IMG in terms of precipitating agents, clinical presentations, and prognosis. After the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews, we searched MEDLINE and EMBASE for all peer-reviewed articles using keywords including "gastritis," "immune checkpoint inhibitor," and "immune-related adverse event" from their inception to December 28, 2021. Twenty-two articles, including 5 observational studies and 17 case reports and case series, were included. Nivolumab, pembrolizumab, and combination therapy with those and cytotoxic T-lymphocyte-associated antigen-4 inhibitor (ipilimumab) were commonly used in those with IMG. 59.8% had epigastric pain, and 50% had erosive gastritis. 87.5% had Common Terminology Criteria for Adverse Events (CTCAE) grade 3 gastritis, and 91.2% received corticosteroids. Recurrence was noted in 16.7%, and only 1 expiration was noted. 4.3% had positive helicobacter pylori and cytomegalovirus from the gastric specimen. Similar to immune-related colitis, patients with IMG may have a favorable prognosis with a better response to immune checkpoint inhibitors if treated appropriately. The diagnosis of IMG is made by exclusion, and a thorough workup is necessary to rule out concurrent helicobacter pylori and cytomegalovirus involvement. Further studies are critical for a better understanding of this complication.

Severe immune checkpoint inhibitor-associated gastritis: A case series and literature review

Background and study aims  Recent advances in cancer treatment have involved the clinical application of immune checkpoint inhibitors (ICIs) for various type of cancers. The adverse events associated with ICIs are generally referred to as immune-related adverse events (irAEs). Gastrointestinal irAEs are a major disorder, but gastritis is not frequently observed. The aims of this study were to elucidate the clinical, endoscopic, and histological characteristics of irAE gastritis. Patients and methods  Information on patients treated with ICIs were collected from a single institute over 3 years. IrAE gastritis was identified based on the clinical course and endoscopic and histopathological findings. Of the 359 patients treated with ICIs, four cases of irAE gastritis were identified in clinical records from the endoscopy unit. The endoscopic and histopathological findings were analyzed, and further immunohistochemical studies with immune subtype markers and programmed cell death ligand-1 (PD-L1) antibody were conducted. Results  Among four patients with irAE gastritis, the remarkable endoscopic characteristics were network-pattern erosion, erythematous and edematous mucosa with thick purulent discharge, and fragile mucosa. Corresponding histological features were fibrinopurulent exudate, severe inflammatory cell infiltration, and epithalaxia, respectively. The PD-L1 expression rate was ≥ 1 % in the gastric tissue of all patients with gastritis. These patients were treated with prednisolone (PSL) and their symptoms improved within a few days to 2 weeks. Conclusions  IrAE gastritis were characterized by specific endoscopic findings. The appropriate endoscopic diagnosis may lead to effective treatment with PSL.

Immune Checkpoint Inhibitor-Associated Colitis: From Mechanism to Management

Immune checkpoint inhibitors (ICIs), as one of the innovative types of immunotherapies, including programmed cell death-1 (PD-1), programmed cell death-ligand 1 (PD-L1), and cytotoxic T lymphocyte antigen 4 (CTLA-4) inhibitors, have obtained unprecedented benefit in multiple malignancies. However, the immune response activation in the body organs could arise immune-related adverse events (irAEs). Checkpoint inhibitor colitis (CIC) is the most widely reported irAEs. However, some obscure problems, such as the mechanism concerning gut microbiota, the confusing differential diagnosis with inflammatory bowel disease (IBD), the optimal steroid schedule, the reintroduction of ICIs, and the controversial prognosis features, influence the deep understanding and precise diagnosis and management of CIC. Herein, we based on these problems and comprehensively summarized the relevant studies of CIC in patients with NSCLC, further discussing the future research direction of this specific pattern of irAEs.